That's bizarre ... given my limited knowledge of bicycle maintenance, I'd guess it was an underlying structural problem with the stem. I've seen pictures on here of steel frames cracking or flaking, so maybe something similar was happening, 'cept it wasn't on the outside?

ha wrote:if in doubt, throw it out. im into recyclling sure, but not if it is dangerous to my cycling..

*distracts from thread topic*

Hm, what about junkyards/scrap metal recycling, though? Er ... that is, unless you have a carbon bike stem. Haven't noticed how many made out of carbon or meta, but a Google search tells me that it's not rare.